Theloss of cells with a high priority is more critical than that of cells with a low priority. If two cells are identical in their other characteristics, then the lower priority cell may be
If the Cell Loss Priority is a 0, then the cell may not be discarded; in the case of a 1, it may be discarded if necessary. The DE bit has a similar function in Frame Relay. The Cell Loss Priority data field of ATM corresponds to the Segment Priority (SP) data field in the DQDB header.